The overarching objective of the University Of Colorado Anschutz Medical Campus Specialized Center Of Research on Sex Differences (UCAMC SCOR) is to develop an interdisciplinary and translational research program to advance the understanding of the Bioenergetic and Metabolic Consequences of the Loss of Gonadal Function. There is compelling evidence from studies of laboratory animals that gonadectomy causes a dramatic decrease of 30-80% in spontaneous physical activity in males and females. Even more intriguing is the observation that this results in excess weight gain, a marked increase in visceral fat, and metabolic dysfunction in female animals but not males. If such findings are relevant to humans, the age related decline in gonadal function may be an important independent determinant of disease risk. Moreover, this would be expected to have a greater adverse effect on the health of women than men, because the loss of gonadal function occurs at an earlier age in women. There will be three SCOR Research Projects to advance novel research in this area: 1) Project I (clinical): Bioenergetic and Metabolic Consequences of the Loss of Ovarian Function in Women (PI: W Kohrt); 2) Project II (preclinical): Effects of Pre-existing Obesity on Consequences of the Loss of Ovarian Function (PI: P MacLean); and 3) Project III (basic): Sex Hormones Differentially Regulate Production of Distinct Adipocyte Populations (PI: D Klemm). The Administrative Core will contribute to the success of the SCOR by: 1) providing scientific leadership for a focused translational and transdisciplinary research program on the consequences of the loss of gonadal function; 2) monitoring the productivity of SCOR Research Projects; 3) expanding the scope of the SCOR through an Ancillary Projects program; 4) expanding the cadre of investigators conducting research on the gonadal regulation of energy balance and metabolism through the Ancillary Projects program; 5) integrating activities of the SCOR with closely partnered programs at UCAMC, including the Center on Aging, the BIRCWH, the Center for Women's Health Research, the Nutrition and Obesity Research Center, the Women's Reproductive Health Research Career Development program, and the Colorado Clinical and Translational Science Institute; 6) providing biostatistical and data management support for the SCOR research projects; and 7) providing administrative support for financial oversight, regulatory oversight, and scheduling and general management of SCOR activities.